


LESS(1)                                                   LESS(1)


NNAAMMEE
       less - opposite of more

SSYYNNOOPPSSIISS
       lleessss --??
       lleessss ----hheellpp
       lleessss --VV
       lleessss ----vveerrssiioonn
       lleessss [[--[[++]]aaBBccCCddeeEEffggGGiiIImmMMnnNNqqQQrrssSSuuUUVVwwXX]]
            [[--bb _b_u_f_s]] [[--hh _l_i_n_e_s]] [[--jj _l_i_n_e]] [[--kk _k_e_y_f_i_l_e]]
            [[--{{ooOO}} _l_o_g_f_i_l_e]] [[--pp _p_a_t_t_e_r_n]] [[--PP _p_r_o_m_p_t]] [[--tt _t_a_g]]
            [[--TT _t_a_g_s_f_i_l_e]] [[--xx _t_a_b]] [[--yy _l_i_n_e_s]] [[--[[zz]] _l_i_n_e_s]]
            [[++[[++]]_c_m_d]] [[----]] [[_f_i_l_e_n_a_m_e]]......
       (See  the OPTIONS section for alternate option syntax with
       long option names.)


DDEESSCCRRIIPPTTIIOONN
       _L_e_s_s is a program similar to _m_o_r_e (1),  but  which  allows
       backward movement in the file as well as forward movement.
       Also, _l_e_s_s does not have to read  the  entire  input  file
       before  starting,  so  with large input files it starts up
       faster than text editors like _v_i (1).  _L_e_s_s  uses  termcap
       (or  terminfo on some systems), so it can run on a variety
       of terminals.  There is even limited support for  hardcopy
       terminals.  (On a hardcopy terminal, lines which should be
       printed at the top of  the  screen  are  prefixed  with  a
       caret.)

       Commands  are  based on both _m_o_r_e and _v_i_.  Commands may be
       preceded by a decimal number, called N in the descriptions
       below.  The number is used by some commands, as indicated.


CCOOMMMMAANNDDSS
       In the following descriptions, ^X  means  control-X.   ESC
       stands for the ESCAPE key; for example ESC-v means the two
       character sequence "ESCAPE", then "v".

       h or H Help: display a summary of these commands.  If  you
              forget all the other commands, remember this one.

       SPACE or ^V or f or ^F
              Scroll  forward  N  lines,  default one window (see
              option -z below).  If N is  more  than  the  screen
              size, only the final screenful is displayed.  Warn-
              ing: some systems use ^V as a  special  literaliza-
              tion character.

       z      Like  SPACE,  but if N is specified, it becomes the
              new window size.

       ESC-SPACE
              Like SPACE, but scrolls a full screenful,  even  if



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LESS(1)                                                   LESS(1)


              it reaches end-of-file in the process.

       RETURN or ^N or e or ^E or j or ^J
              Scroll  forward  N  lines, default 1.  The entire N
              lines are displayed, even if N  is  more  than  the
              screen size.

       d or ^D
              Scroll  forward  N  lines,  default one half of the
              screen size.  If N is specified, it becomes the new
              default for subsequent d and u commands.

       b or ^B or ESC-v
              Scroll  backward  N  lines, default one window (see
              option -z below).  If N is  more  than  the  screen
              size, only the final screenful is displayed.

       w      Like  ESC-v,  but if N is specified, it becomes the
              new window size.

       y or ^Y or ^P or k or ^K
              Scroll backward N lines, default 1.  The  entire  N
              lines  are  displayed,  even  if N is more than the
              screen size.  Warning: some systems  use  ^Y  as  a
              special job control character.

       u or ^U
              Scroll  backward  N  lines, default one half of the
              screen size.  If N is specified, it becomes the new
              default for subsequent d and u commands.

       ESC-) or RIGHTARROW
              Scroll  horizontally right N characters, default 8.
              This behaves best if you also  set  the  -S  option
              (chop  lines).   Note  that  if you wish to enter a
              number N,  you  must  use  ESC-),  not  RIGHTARROW,
              because  the  arrow  is  taken to be a line editing
              command (see the LINE EDITING section).

       ESC-( or LEFTARROW
              Scroll horizontally left N characters, default 8.

       r or ^R or ^L
              Repaint the screen.

       R      Repaint the screen, discarding any buffered  input.
              Useful  if  the  file is changing while it is being
              viewed.

       F      Scroll forward, and keep trying to  read  when  the
              end  of  file  is  reached.   Normally this command
              would be used when already at the end of the  file.
              It  is a way to monitor the tail of a file which is
              growing while it is being viewed.  (The behavior is



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LESS(1)                                                   LESS(1)


              similar to the "tail -f" command.)

       g or < or ESC-<
              Go  to  line N in the file, default 1 (beginning of
              file).  (Warning: this may be slow if N is  large.)

       G or > or ESC->
              Go  to  line  N in the file, default the end of the
              file.  (Warning: this may be slow if N is large, or
              if  N  is  not specified and standard input, rather
              than a file, is being read.)

       p or % Go to a position N percent into the file.  N should
              be between 0 and 100.

       {      If  a  left  curly  bracket appears in the top line
              displayed on the screen, the { command will  go  to
              the  matching  right  curly  bracket.  The matching
              right curly bracket is  positioned  on  the  bottom
              line of the screen.  If there is more than one left
              curly bracket on the top line, a number  N  may  be
              used to specify the N-th bracket on the line.

       }      If a right curly bracket appears in the bottom line
              displayed on the screen, the } command will  go  to
              the matching left curly bracket.  The matching left
              curly bracket is positioned on the top line of  the
              screen.   If  there  is  more  than one right curly
              bracket on the top line, a number N may be used  to
              specify the N-th bracket on the line.

       (      Like  {,  but  applies  to  parentheses rather than
              curly brackets.

       )      Like }, but  applies  to  parentheses  rather  than
              curly brackets.

       [      Like  {, but applies to square brackets rather than
              curly brackets.

       ]      Like }, but applies to square brackets rather  than
              curly brackets.

       ESC-^F Followed  by  two characters, acts like {, but uses
              the two characters  as  open  and  close  brackets,
              respectively.   For  example, "ESC ^F < >" could be
              used to go forward to the > which matches the <  in
              the top displayed line.

       ESC-^B Followed  by  two characters, acts like }, but uses
              the two characters  as  open  and  close  brackets,
              respectively.   For  example, "ESC ^B < >" could be
              used to go backward to the < which matches the > in
              the bottom displayed line.



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LESS(1)                                                   LESS(1)


       m      Followed by any lowercase letter, marks the current
              position with that letter.

       '      (Single quote.)  Followed by any lowercase  letter,
              returns to the position which was previously marked
              with  that  letter.   Followed  by  another  single
              quote,  returns  to  the position at which the last
              "large" movement command was executed.  Followed by
              a ^ or $, jumps to the beginning or end of the file
              respectively.  Marks are preserved when a new  file
              is examined, so the ' command can be used to switch
              between input files.

       ^X^X   Same as single quote.

       /pattern
              Search forward in the file for the N-th  line  con-
              taining the pattern.  N defaults to 1.  The pattern
              is a regular expression, as recognized by _e_d_.   The
              search starts at the second line displayed (but see
              the -a and -j options, which change this).

              Certain characters are special if  entered  at  the
              beginning  of  the pattern; they modify the type of
              search rather than become part of the pattern:

              ^N or !
                     Search for lines which do NOT match the pat-
                     tern.

              ^E or *
                     Search  multiple  files.   That  is,  if the
                     search reaches the END of the  current  file
                     without  finding a match, the search contin-
                     ues in the next file  in  the  command  line
                     list.

              ^F or @
                     Begin  the  search  at the first line of the
                     FIRST file in the command line list, regard-
                     less  of  what is currently displayed on the
                     screen or the  settings  of  the  -a  or  -j
                     options.

              ^K     Highlight any text which matches the pattern
                     on the current screen, but don't move to the
                     first match (KEEP current position).

              ^R     Don't interpret regular expression metachar-
                     acters; that is, do a simple textual compar-
                     ison.

       ?pattern
              Search  backward  in  the  file  for  the N-th line



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LESS(1)                                                   LESS(1)


              containing the pattern.  The search starts  at  the
              line immediately before the top line displayed.

              Certain characters are special as in the / command:

              ^N or !
                     Search for lines which do NOT match the pat-
                     tern.

              ^E or *
                     Search  multiple  files.   That  is,  if the
                     search reaches the beginning of the  current
                     file  without  finding  a  match, the search
                     continues in the previous file in  the  com-
                     mand line list.

              ^F or @
                     Begin  the  search  at  the last line of the
                     last file in the command line list,  regard-
                     less  of  what is currently displayed on the
                     screen or the  settings  of  the  -a  or  -j
                     options.

              ^K     As in forward searches.

              ^R     As in forward searches.

       ESC-/pattern
              Same as "/*".

       ESC-?pattern
              Same as "?*".

       n      Repeat  previous  search,  for N-th line containing
              the last pattern.  If the previous search was modi-
              fied  by  ^N,  the search is made for the N-th line
              NOT containing the pattern.  If the previous search
              was  modified  by  ^E,  the search continues in the
              next (or previous) file if  not  satisfied  in  the
              current  file.  If the previous search was modified
              by ^R, the search is  done  without  using  regular
              expressions.   There  is  no effect if the previous
              search was modified by ^F or ^K.

       N      Repeat previous search, but in the  reverse  direc-
              tion.

       ESC-n  Repeat  previous  search,  but crossing file bound-
              aries.  The effect is as  if  the  previous  search
              were modified by *.

       ESC-N  Repeat  previous  search, but in the reverse direc-
              tion and crossing file boundaries.




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LESS(1)                                                   LESS(1)


       ESC-u  Undo search highlighting.  Turn off highlighting of
              strings  matching  the  current search pattern.  If
              highlighting is already off because of  a  previous
              ESC-u  command,  turn  highlighting  back  on.  Any
              search command will also turn highlighting back on.
              (Highlighting  can also be disabled by toggling the
              -G option; in that case search commands do not turn
              highlighting back on.)

       :e [filename]
              Examine  a  new  file.  If the filename is missing,
              the "current" file (see  the  :n  and  :p  commands
              below)  from  the list of files in the command line
              is re-examined.  A percent sign (%) in the filename
              is  replaced  by  the  name of the current file.  A
              pound sign (#) is replaced by the name of the  pre-
              viously  examined  file.   However, two consecutive
              percent signs are simply  replaced  with  a  single
              percent  sign.  This allows you to enter a filename
              that contains a percent sign in  the  name.   Simi-
              larly,  two  consecutive  pound  signs are replaced
              with a single pound sign.  The filename is inserted
              into  the command line list of files so that it can
              be seen by subsequent :n and :p commands.   If  the
              filename  consists  of  several files, they are all
              inserted into the list of files and the  first  one
              is  examined.  If the filename contains one or more
              spaces, the entire filename should be  enclosed  in
              double quotes (also see the -" option).

       ^X^V or E
              Same as :e.  Warning: some systems use ^V as a spe-
              cial literalization character.   On  such  systems,
              you may not be able to use ^V.

       :n     Examine the next file (from the list of files given
              in the command line).  If a number N is  specified,
              the N-th next file is examined.

       :p     Examine the previous file in the command line list.
              If a number N is specified, the N-th previous  file
              is examined.

       :x     Examine  the  first  file in the command line list.
              If a number N is specified, the N-th  file  in  the
              list is examined.

       :d     Remove the current file from the list of files.

       = or ^G or :f
              Prints   some  information  about  the  file  being
              viewed, including its name and the line number  and
              byte offset of the bottom line being displayed.  If
              possible, it also prints the length  of  the  file,



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LESS(1)                                                   LESS(1)


              the  number of lines in the file and the percent of
              the file above the last displayed line.

       -      Followed by one of the command line option  letters
              (see  OPTIONS  below), this will change the setting
              of that option and print a message  describing  the
              new  setting.  If a ^P (CONTROL-P) is entered imme-
              diately after the dash, the setting of  the  option
              is  changed  but  no  message  is  printed.  If the
              option letter has a numeric value (such  as  -b  or
              -h),  or  a  string value (such as -P or -t), a new
              value may be entered after the option  letter.   If
              no  new  value is entered, a message describing the
              current setting is printed and nothing is  changed.

       --     Like  the  -  command, but takes a long option name
              (see OPTIONS below) rather  than  a  single  option
              letter.   You  must  press  RETURN after typing the
              option name.  A ^P  immediately  after  the  second
              dash  suppresses  printing  of a message describing
              the new setting, as in the - command.

       -+     Followed by one of the command line option  letters
              this  will  reset the option to its default setting
              and print a message  describing  the  new  setting.
              (The  "-+_X" command does the same thing as "-+_X" on
              the command line.)  This does not work for  string-
              valued options.

       --+    Like  the  -+ command, but takes a long option name
              rather than a single option letter.

       -!     Followed by one of the command line option letters,
              this will reset the option to the "opposite" of its
              default setting and print a message describing  the
              new  setting.   This  does  not work for numeric or
              string-valued options.

       --!    Like the -! command, but takes a long  option  name
              rather than a single option letter.

       _      (Underscore.)   Followed by one of the command line
              option letters, this will print a message  describ-
              ing  the  current setting of that option.  The set-
              ting of the option is not changed.

       __     (Double underscore.)  Like the _ (underscore)  com-
              mand,  but  takes  a long option name rather than a
              single option letter.  You must press RETURN  after
              typing the option name.

       +cmd   Causes the specified cmd to be executed each time a
              new file is examined.  For example, +G causes  _l_e_s_s
              to  initially display each file starting at the end



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LESS(1)                                                   LESS(1)


              rather than the beginning.

       V      Prints the version number of _l_e_s_s being run.

       q or Q or :q or :Q or ZZ
              Exits _l_e_s_s_.

       The following four commands  may  or  may  not  be  valid,
       depending on your particular installation.


       v      Invokes  an  editor  to edit the current file being
              viewed.  The editor is taken from  the  environment
              variable  VISUAL if defined, or EDITOR if VISUAL is
              not defined, or defaults to "vi" if neither  VISUAL
              nor  EDITOR is defined.  See also the discussion of
              LESSEDIT under the section on PROMPTS below.

       ! shell-command
              Invokes a shell to run the shell-command given.   A
              percent  sign (%) in the command is replaced by the
              name of the current file.   A  pound  sign  (#)  is
              replaced  by  the  name  of the previously examined
              file.  "!!" repeats the last  shell  command.   "!"
              with  no  shell command simply invokes a shell.  On
              Unix systems, the shell is taken from the  environ-
              ment  variable  SHELL, or defaults to "sh".  On MS-
              DOS and OS/2 systems, the shell is the normal  com-
              mand processor.

       | <m> shell-command
              <m> represents any mark letter.  Pipes a section of
              the input file to the  given  shell  command.   The
              section  of  the  file  to  be piped is between the
              first line on the current screen and  the  position
              marked  by  the  letter.  <m> may also be ^ or $ to
              indicate beginning or end of file respectively.  If
              <m> is . or newline, the current screen is piped.

       s filename
              Save  the  input to a file.  This only works if the
              input is a pipe, not an ordinary file.


OOPPTTIIOONNSS
       Command line options are described  below.   Most  options
       may be changed while _l_e_s_s is running, via the "-" command.

       Most options may be given in one of two  forms:  either  a
       dash  followed  by a single letter, or two dashes followed
       by a long option name.  A long option name may be abbrevi-
       ated  as  long  as  the  abbreviation is unambiguous.  For
       example, --quit-at-eof may be abbreviated --quit, but  not
       --qui,  since  both  --quit-at-eof  and --quiet begin with



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LESS(1)                                                   LESS(1)


       --qui.  Some long option names are in uppercase,  such  as
       --QUIT-AT-EOF,   as  distinct  from  --quit-at-eof.   Such
       option names need only have their  first  letter  capital-
       ized;  the  remainder  of  the name may be in either case.
       For example, --Quit-at-eof is equivalent to --QUIT-AT-EOF.

       Options  are  also  taken  from  the  environment variable
       "LESS".  For example, to avoid typing "less -options  ..."
       each time _l_e_s_s is invoked, you might tell _c_s_h_:

       setenv LESS "-options"

       or if you use _s_h_:

       LESS="-options"; export LESS

       On  MS-DOS,  you  don't  need  the  quotes, but you should
       replace any percent signs in the options string by  double
       percent signs.

       The  environment  variable  is  parsed  before the command
       line, so command line options override the  LESS  environ-
       ment variable.  If an option appears in the LESS variable,
       it can be reset to its default value on the  command  line
       by beginning the command line option with "-+".

       For options like -P or -D which take a following string, a
       dollar sign ($) must be used to  signal  the  end  of  the
       string.  For example, to set two -D options on MS-DOS, you
       must have a dollar sign between them, like this:

       LESS="-Dn9.1$-Ds4.1"


       -? or --help
              This option displays  a  summary  of  the  commands
              accepted  by  _l_e_s_s  (the  same  as  the h command).
              (Depending on how your shell interprets  the  ques-
              tion  mark,  it may be necessary to quote the ques-
              tion mark, thus: "-\?".)

       -a or --search-skip-screen
              Causes searches to start after the last  line  dis-
              played  on the screen, thus skipping all lines dis-
              played on the screen.  By default,  searches  start
              at the second line on the screen (or after the last
              found line; see the -j option).

       -b_n or --buffers=_n
              Specifies the number of buffers _l_e_s_s will  use  for
              each  file.   Buffers  are  1K,  and  by default 10
              buffers are used for each file (except if the  file
              is a pipe; see the -B option).  The number _n speci-
              fies a different number of buffers to use.



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LESS(1)                                                   LESS(1)


       -B or --auto-buffers
              By default, when data is read from a pipe,  buffers
              are  allocated automatically as needed.  If a large
              amount of data is read  from  the  pipe,  this  can
              cause  a  large  amount  of memory to be allocated.
              The -B option disables this automatic allocation of
              buffers  for  pipes,  so  that  only  the number of
              buffers specified by the -b option are used.  Warn-
              ing:  use  of  -B  can result in erroneous display,
              since only the most recently  viewed  part  of  the
              file is kept in memory; any earlier data is lost.

       -c or --clear-screen
              Causes  full screen repaints to be painted from the
              top line down.  By default,  full  screen  repaints
              are  done  by  scrolling  from  the  bottom  of the
              screen.

       -C or --CLEAR-SCREEN
              The -C option is like -c, but the screen is cleared
              before it is repainted.

       -d or --dumb
              The -d option suppresses the error message normally
              displayed if the terminal is dumb; that  is,  lacks
              some  important  capability, such as the ability to
              clear the screen or scroll backward.  The -d option
              does not otherwise change the behavior of _l_e_s_s on a
              dumb terminal).

       -Dxx_c_o_l_o_r or --color=xx_c_o_l_o_r
              [MS-DOS only] Sets the color of the text displayed.
              xx  is  a single character which selects the type of
              text whose color is being set:  n=normal,  s=stand-
              out,  d=bold,  u=underlined,  k=blink.   _c_o_l_o_r is a
              pair of numbers separated by a period.   The  first
              number  selects the foreground color and the second
              selects the background color of the text.  A single
              number _N is the same as _N_._0.

       -e or --quit-at-eof
              Causes  _l_e_s_s  to automatically exit the second time
              it reaches end-of-file.  By default, the  only  way
              to exit _l_e_s_s is via the "q" command.

       -E or --QUIT-AT-EOF
              Causes _l_e_s_s to automatically exit the first time it
              reaches end-of-file.

       -f or --force
              Forces non-regular files to be opened.  (A non-reg-
              ular file is a directory or a device special file.)
              Also suppresses the warning message when  a  binary
              file  is  opened.   By default, _l_e_s_s will refuse to



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LESS(1)                                                   LESS(1)


              open non-regular files.

       -g or --hilite-search
              Normally, _l_e_s_s will  highlight  ALL  strings  which
              match  the  last  search  command.   The  -g option
              changes this behavior to highlight only the partic-
              ular string which was found by the last search com-
              mand.  This can cause _l_e_s_s to run  somewhat  faster
              than the default.

       -G or --HILITE-SEARCH
              The   -G  option  suppresses  all  highlighting  of
              strings found by search commands.

       -h_n or ---max-back-scroll=_n
              Specifies a maximum number of lines to scroll back-
              ward.   If  it is necessary to scroll backward more
              than _n lines, the screen is repainted in a  forward
              direction  instead.  (If the terminal does not have
              the ability to scroll backward, -h0 is implied.)

       -i or --ignore-case
              Causes searches to ignore case; that is,  uppercase
              and   lowercase  are  considered  identical.   This
              option is ignored if any uppercase  letters  appear
              in the search pattern; in other words, if a pattern
              contains uppercase letters, then that  search  does
              not ignore case.

       -I or --IGNORE-CASE
              Like  -i, but searches ignore case even if the pat-
              tern contains uppercase letters.

       -j_n or --jump-target=_n
              Specifies a line on the screen where  the  "target"
              line  is  to  be  positioned.  A target line is the
              object of a text search, tag search, jump to a line
              number,  jump  to  a  file percentage, or jump to a
              marked position.  The screen line is specified by a
              number:  the  top line on the screen is 1, the next
              is 2, and so on.  The number  may  be  negative  to
              specify  a  line  relative  to  the  bottom  of the
              screen: the bottom line on the screen  is  -1,  the
              second  to  the bottom is -2, and so on.  If the -j
              option is used, searches begin at the line  immedi-
              ately after the target line.  For example, if "-j4"
              is used, the target line is the fourth line on  the
              screen,  so searches begin at the fifth line on the
              screen.

       -k_f_i_l_e_n_a_m_e or --lesskey-file=_f_i_l_e_n_a_m_e
              Causes _l_e_s_s to open and interpret the named file as
              a  _l_e_s_s_k_e_y  (1)  file.   Multiple -k options may be
              specified.  If the LESSKEY environment variable  is



                     Version 340: 27 Apr 1999                  11





LESS(1)                                                   LESS(1)


              set,  or  if  a lesskey file is found in a standard
              place (see KEY BINDINGS), it  is  also  used  as  a
              _l_e_s_s_k_e_y file.

       -m or --long-prompt
              Causes  _l_e_s_s  to prompt verbosely (like _m_o_r_e), with
              the  percent  into  the  file.   By  default,  _l_e_s_s
              prompts with a colon.

       -M or --LONG-PROMPT
              Causes  _l_e_s_s  to  prompt  even  more verbosely than
              _m_o_r_e_.

       -n or --line-numbers
              Suppresses line numbers.  The default (to use  line
              numbers)  may cause _l_e_s_s to run more slowly in some
              cases, especially with a  very  large  input  file.
              Suppressing  line  numbers  with the -n option will
              avoid this problem.  Using line numbers means:  the
              line number will be displayed in the verbose prompt
              and in the = command, and the v command  will  pass
              the current line number to the editor (see also the
              discussion of LESSEDIT in PROMPTS below).

       -N or --LINE-NUMBERS
              Causes a line number to be displayed at the  begin-
              ning of each line in the display.

       -o_f_i_l_e_n_a_m_e or --log-file=_f_i_l_e_n_a_m_e
              Causes  _l_e_s_s to copy its input to the named file as
              it is being viewed.  This  applies  only  when  the
              input file is a pipe, not an ordinary file.  If the
              file already exists, _l_e_s_s will ask for confirmation
              before overwriting it.

       -O_f_i_l_e_n_a_m_e or --LOG-FILE=_f_i_l_e_n_a_m_e
              The  -O option is like -o, but it will overwrite an
              existing file without asking for confirmation.

              If no log file has been specified, the  -o  and  -O
              options  can  be used from within _l_e_s_s to specify a
              log file.  Without a file name,  they  will  simply
              report  the  name of the log file.  The "s" command
              is equivalent to specifying -o from within _l_e_s_s_.

       -p_p_a_t_t_e_r_n or --pattern=_p_a_t_t_e_r_n
              The -p option on the command line is equivalent  to
              specifying  +/_p_a_t_t_e_r_n;  that  is,  it tells _l_e_s_s to
              start at the first occurrence  of  _p_a_t_t_e_r_n  in  the
              file.

       -P_p_r_o_m_p_t or --prompt=_p_r_o_m_p_t
              Provides a way to tailor the three prompt styles to
              your own preference.  This option would normally be



                     Version 340: 27 Apr 1999                  12





LESS(1)                                                   LESS(1)


              put  in  the LESS environment variable, rather than
              being typed in with each  _l_e_s_s  command.   Such  an
              option  must  either be the last option in the LESS
              variable, or be terminated by a dollar  sign.   -Ps
              followed  by  a  string changes the default (short)
              prompt to that string.  -Pm changes the medium (-m)
              prompt.   -PM  changes  the  long (-M) prompt.  -Ph
              changes  the  prompt  for  the  help  screen.   -P=
              changes  the message printed by the = command.  All
              prompt strings consist of a sequence of letters and
              special  escape  sequences.   See  the  section  on
              PROMPTS for more details.

       -q or --quiet or --silent
              Causes moderately "quiet" operation:  the  terminal
              bell  is  not  rung if an attempt is made to scroll
              past the end of the file or before the beginning of
              the  file.  If the terminal has a "visual bell", it
              is used instead.  The bell will be rung on  certain
              other  errors, such as typing an invalid character.
              The default is to ring the  terminal  bell  in  all
              such cases.

       -Q or --QUIET or --SILENT
              Causes totally "quiet" operation: the terminal bell
              is never rung.

       -r or --raw-control-chars
              Causes "raw" control characters  to  be  displayed.
              The  default is to display control characters using
              the caret notation; for example, a control-A (octal
              001)  is  displayed  as "^A".  Warning: when the -r
              option is used,  _l_e_s_s  cannot  keep  track  of  the
              actual appearance of the screen (since this depends
              on how the screen responds to each type of  control
              character).   Thus,  various  display  problems may
              result, such as long lines being split in the wrong
              place.

       -s or --squeeze-blank-lines
              Causes  consecutive blank lines to be squeezed into
              a single blank line.  This is useful  when  viewing
              _n_r_o_f_f output.

       -S or --chop-long-lines
              Causes  lines  longer  than  the screen width to be
              chopped rather than folded.  That is, the remainder
              of a long line is simply discarded.  The default is
              to fold long lines; that is, display the  remainder
              on the next line.

       -t_t_a_g or --tag=_t_a_g
              The  -t option, followed immediately by a TAG, will
              edit the file containing that  tag.   For  this  to



                     Version 340: 27 Apr 1999                  13





LESS(1)                                                   LESS(1)


              work,  there  must  be  a file called "tags" in the
              current directory, which was  previously  built  by
              the  _c_t_a_g_s  (1)  command.   This option may also be
              specified from within _l_e_s_s (using the - command) as
              a way of examining a new file.  The command ":t" is
              equivalent to specifying -t from within _l_e_s_s_.

       -T_t_a_g_s_f_i_l_e or --tag-file=_t_a_g_s_f_i_l_e
              Specifies a tags file to be used instead of "tags".

       -u or --underline-special
              Causes   backspaces  and  carriage  returns  to  be
              treated as printable characters; that is, they  are
              sent to the terminal when they appear in the input.

       -U or --UNDERLINE-SPECIAL
              Causes backspaces, tabs and carriage returns to  be
              treated  as  control  characters; that is, they are
              handled as specified by the -r option.

              By  default,  if  neither  -u  nor  -U  is   given,
              backspaces  which  appear adjacent to an underscore
              character are  treated  specially:  the  underlined
              text  is  displayed  using  the terminal's hardware
              underlining  capability.   Also,  backspaces  which
              appear between two identical characters are treated
              specially: the overstruck text is printed using the
              terminal's  hardware  boldface  capability.   Other
              backspaces are deleted, along  with  the  preceding
              character.   Carriage  returns immediately followed
              by a newline are deleted.  other  carriage  returns
              are  handled  as  specified by the -r option.  Text
              which is overstruck or underlined can  be  searched
              for if neither -u nor -U is in effect.

       -V or --version
              Displays the version number of _l_e_s_s_.

       -w or --hilite-unread
              Temporarily highlights the first "new" line after a
              forward movement of a full page.  The  first  "new"
              line  is  the  line  immediately following the line
              previously at the bottom of the screen.  The  high-
              light  is  removed at the next command which causes
              movement.

       -W or --HILITE-UNREAD
              Like -w, but temporarily highlights the  first  new
              line after any forward movement command larger than
              one line.

       -x_n or --tabs=_n
              Sets tab stops every _n positions.  The default  for
              _n is 8.



                     Version 340: 27 Apr 1999                  14





LESS(1)                                                   LESS(1)


       -X or --no-init
              Disables  sending  the  termcap  initialization and
              deinitialization strings to the terminal.  This  is
              sometimes  desirable if the deinitialization string
              does  something  unnecessary,  like  clearing   the
              screen.

       -y_n or --max-forw-scroll=_n
              Specifies  a maximum number of lines to scroll for-
              ward.  If it is necessary to  scroll  forward  more
              than _n lines, the screen is repainted instead.  The
              -c or -C option may be used to repaint from the top
              of  the screen if desired.  By default, any forward
              movement causes scrolling.

       -[z]_n or --window=_n
              Changes the default  scrolling  window  size  to  _n
              lines.   The default is one screenful.  The z and w
              commands can also be  used  to  change  the  window
              size.   The  "z"  may  be omitted for compatibility
              with _m_o_r_e_.  If the number _n is negative,  it  indi-
              cates  _n  lines  less than the current screen size.
              For example, if the screen is 24 lines,  _-_z_-_4  sets
              the scrolling window to 20 lines.  If the screen is
              resized to 40 lines, the scrolling window automati-
              cally changes to 36 lines.

       -"_c_c or --quotes=_c_c
              Changes  the  filename quoting character.  This may
              be necessary if you are trying to name a file which
              contains  both  spaces  and quote characters.  Fol-
              lowed by a single character, this changes the quote
              character  to that character.  Filenames containing
              a space should then be surrounded by that character
              rather  than  by  double  quotes.   Followed by two
              characters, changes the open  quote  to  the  first
              character,  and the close quote to the second char-
              acter.  Filenames containing a space should then be
              preceded  by  the open quote character and followed
              by the close quote character.  Note that even after
              the  quote  characters  are  changed,  this  option
              remains -" (a dash followed by a double quote).

       -~ or --tilde
              Normally lines after end of file are displayed as a
              single  tilde  (~).  This option causes lines after
              end of file to be displayed as blank lines.

       --     A command line argument of "--" marks  the  end  of
              option arguments.  Any arguments following this are
              interpreted as filenames.  This can be useful  when
              viewing a file whose name begins with a "-" or "+".

       +      If  a  command  line  option  begins  with  ++,  the



                     Version 340: 27 Apr 1999                  15





LESS(1)                                                   LESS(1)


              remainder  of that option is taken to be an initial
              command to _l_e_s_s_.  For example,  +G  tells  _l_e_s_s  to
              start at the end of the file rather than the begin-
              ning, and +/xyz tells it  to  start  at  the  first
              occurrence  of  "xyz"  in  the  file.  As a special
              case, +<number> acts like +<number>g; that  is,  it
              starts  the  display  at  the specified line number
              (however, see the  caveat  under  the  "g"  command
              above).   If the option starts with ++, the initial
              command applies to every  file  being  viewed,  not
              just the first one.  The + command described previ-
              ously may also be used to set (or change)  an  ini-
              tial command for every file.


LLIINNEE EEDDIITTIINNGG
       When  entering  command  line  at the bottom of the screen
       (for example, a filename for the :e command, or  the  pat-
       tern  for  a  search command), certain keys can be used to
       manipulate the command line.  Most commands have an alter-
       nate  form in [ brackets ] which can be used if a key does
       not exist on a particular keyboard.  (The bracketed  forms
       do  not work in the MS-DOS version.)  Any of these special
       keys may be entered literally by  preceding  it  with  the
       "literal"  character, either ^V or ^A.  A backslash itself
       may also be entered literally by entering two backslashes.

       LEFTARROW [ ESC-h ]
              Move the cursor one space to the left.

       RIGHTARROW [ ESC-l ]
              Move the cursor one space to the right.

       ^LEFTARROW [ ESC-b or ESC-LEFTARROW ]
              (That  is,  CONTROL  and LEFTARROW simultaneously.)
              Move the cursor one word to the left.

       ^RIGHTARROW [ ESC-w or ESC-RIGHTARROW ]
              (That is, CONTROL and  RIGHTARROW  simultaneously.)
              Move the cursor one word to the right.

       HOME [ ESC-0 ]
              Move the cursor to the beginning of the line.

       END [ ESC-$ ]
              Move the cursor to the end of the line.

       BACKSPACE
              Delete  the character to the left of the cursor, or
              cancel the command if the command line is empty.

       DELETE or [ ESC-x ]
              Delete the character under the cursor.




                     Version 340: 27 Apr 1999                  16





LESS(1)                                                   LESS(1)


       ^BACKSPACE [ ESC-BACKSPACE ]
              (That is, CONTROL  and  BACKSPACE  simultaneously.)
              Delete the word to the left of the cursor.

       ^DELETE [ ESC-X or ESC-DELETE ]
              (That   is,  CONTROL  and  DELETE  simultaneously.)
              Delete the word under the cursor.

       UPARROW [ ESC-k ]
              Retrieve the previous command line.

       DOWNARROW [ ESC-j ]
              Retrieve the next command line.

       TAB    Complete the partial filename to the  left  of  the
              cursor.   If it matches more than one filename, the
              first match  is  entered  into  the  command  line.
              Repeated  TABs  will  cycle thru the other matching
              filenames.  If the completed filename is  a  direc-
              tory,  a  "/" is appended to the filename.  (On MS-
              DOS systems, a "\" is appended.)   The  environment
              variable  LESSSEPARATOR  can  be  used to specify a
              different character to append to a directory  name.

       BACKTAB [ ESC-TAB ]
              Like, TAB, but cycles in the reverse direction thru
              the matching filenames.

       ^L     Complete the partial filename to the  left  of  the
              cursor.   If it matches more than one filename, all
              matches are entered into the command line (if  they
              fit).

       ^U (Unix) or ESC (MS-DOS)
              Delete  the entire command line, or cancel the com-
              mand if the command line is  empty.   If  you  have
              changed  your  line-kill character in Unix to some-
              thing other than ^U, that character is used instead
              of ^U.


KKEEYY BBIINNDDIINNGGSS
       You may define your own _l_e_s_s commands by using the program
       _l_e_s_s_k_e_y (1) to create a lesskey file.  This file specifies
       a  set  of command keys and an action associated with each
       key.  You may also use _l_e_s_s_k_e_y to change the  line-editing
       keys (see LINE EDITING), and to set environment variables.
       If the environment variable LESSKEY is set, _l_e_s_s uses that
       as the name of the lesskey file.  Otherwise, _l_e_s_s looks in
       a standard place for the lesskey file:  On  Unix  systems,
       _l_e_s_s  looks  for  a lesskey file called "$HOME/.less".  On
       MS-DOS systems, _l_e_s_s  looks  for  a  lesskey  file  called
       "$HOME/_less",  and  if  it is not found there, then looks
       for  a  lesskey  file  called  "_less"  in  any  directory



                     Version 340: 27 Apr 1999                  17





LESS(1)                                                   LESS(1)


       specified  in the PATH environment variable.  On OS/2 sys-
       tems,   _l_e_s_s   looks   for   a   lesskey    file    called
       "$HOME/less.ini", and if it is not found, then looks for a
       lesskey file called "less.ini" in any directory  specified
       in  the  INIT  environment  variable,  and if it not found
       there, then looks for a lesskey file called "less.ini"  in
       any  directory specified in the PATH environment variable.
       See the _l_e_s_s_k_e_y manual page for more details.


IINNPPUUTT PPRREEPPRROOCCEESSSSOORR
       You may define an "input preprocessor" for  _l_e_s_s_.   Before
       _l_e_s_s  opens a file, it first gives your input preprocessor
       a chance to modify the way the contents of  the  file  are
       displayed.   An input preprocessor is simply an executable
       program (or shell script), which writes  the  contents  of
       the file to a different file, called the replacement file.
       The contents of the replacement file are then displayed in
       place  of  the contents of the original file.  However, it
       will appear to the user as if the original file is opened;
       that  is,  _l_e_s_s  will display the original filename as the
       name of the current file.

       An input preprocessor receives one command line  argument,
       the  original filename, as entered by the user.  It should
       create the replacement file, and when finished, print  the
       name  of  the replacement file to its standard output.  If
       the input preprocessor does not output a replacement file-
       name,  _l_e_s_s  uses the original file, as normal.  The input
       preprocessor is not called when  viewing  standard  input.
       To set up an input preprocessor, set the LESSOPEN environ-
       ment variable to a command line  which  will  invoke  your
       input  preprocessor.  This command line should include one
       occurrence of the string "%s", which will be  replaced  by
       the  filename  when  the  input  preprocessor  command  is
       invoked.

       When _l_e_s_s closes a file opened in such a way, it will call
       another program, called the input postprocessor, which may
       perform any desired clean-up action (such as deleting  the
       replacement  file  created  by  LESSOPEN).   This  program
       receives two command line arguments, the original filename
       as  entered  by  the user, and the name of the replacement
       file.  To set up an input postprocessor, set the LESSCLOSE
       environment  variable  to a command line which will invoke
       your input postprocessor.  It may include two  occurrences
       of  the string "%s"; the first is replaced with the origi-
       nal name of the file and the second with the name  of  the
       replacement file, which was output by LESSOPEN.

       For  example, on many Unix systems, these two scripts will
       allow you to keep files in compressed  format,  but  still
       let _l_e_s_s view them directly:




                     Version 340: 27 Apr 1999                  18





LESS(1)                                                   LESS(1)


       lessopen.sh:
            #! /bin/sh
            case "$1" in
            *.Z) uncompress -c $1  >/tmp/less.$$  2>/dev/null
                 if [ -s /tmp/less.$$ ]; then
                      echo /tmp/less.$$
                 else
                      rm -f /tmp/less.$$
                 fi
                 ;;
            esac

       lessclose.sh:
            #! /bin/sh
            rm $2

       To use these scripts, put them both where they can be exe-
       cuted    and    set     LESSOPEN="lessopen.sh %s",     and
       LESSCLOSE="lessclose.sh %s %s".  More complex LESSOPEN and
       LESSCLOSE scripts may be written to accept other types  of
       compressed files, and so on.

       It  is  also  possible  to set up an input preprocessor to
       pipe the file data directly to _l_e_s_s_, rather  than  putting
       the data into a replacement file.  This avoids the need to
       decompress the entire file before starting to view it.  An
       input  preprocessor that works this way is called an input
       pipe.  An input pipe, instead of writing  the  name  of  a
       replacement file on its standard output, writes the entire
       contents of the replacement file on its  standard  output.
       If  the  input  pipe  does not write any characters on its
       standard output, then there is  no  replacement  file  and
       _l_e_s_s  uses  the original file, as normal.  To use an input
       pipe, make the first character in the LESSOPEN environment
       variable a vertical bar (|) to signify that the input pre-
       processor is an input pipe.

       For example, on many Unix systems, this script  will  work
       like the previous example scripts:

       lesspipe.sh:
            #! /bin/sh
            case "$1" in
            *.Z) uncompress -c $1  2>/dev/null
                 ;;
            esac

       To  use  this  script, put it where it can be executed and
       set LESSOPEN="|lesspipe.sh %s".  When  an  input  pipe  is
       used,  a  LESSCLOSE  postprocessor  can be used, but it is
       usually not necessary since there is no  replacement  file
       to  clean  up.   In  this  case, the replacement file name
       passed to the LESSCLOSE postprocessor is "-".




                     Version 340: 27 Apr 1999                  19





LESS(1)                                                   LESS(1)


NNAATTIIOONNAALL CCHHAARRAACCTTEERR SSEETTSS
       There are three types of characters in the input file:

       normal characters
              can be displayed directly to the screen.

       control characters
              should not be displayed directly, but are  expected
              to  be  found  in  ordinary  text  files  (such  as
              backspace and tab).

       binary characters
              should  not  be  displayed  directly  and  are  not
              expected to be found in text files.

       A "character set" is simply a description of which charac-
       ters are to be considered  normal,  control,  and  binary.
       The LESSCHARSET environment variable may be used to select
       a character set.  Possible values for LESSCHARSET are:

       ascii  The default character set.  BS, TAB,  NL,  CR,  and
              formfeed  are  control  characters,  all chars with
              values between 32 and 126 are normal, and all  oth-
              ers are binary.

       iso8859
              Selects  the  ISO 8859/1 character set.  latin-1 is
              the same as ASCII, except  characters  between  161
              and 255 are treated as normal characters.

       latin1 Same as iso8859.

       dos    Selects a character set appropriate for MS-DOS.

       ebcdic Selects an EBCDIC character set.

       koi8-r Selects a Russian character set.

       next   Selects  a  character set appropriate for NeXT com-
              puters.

       In special cases, it may be desired to tailor _l_e_s_s to  use
       a  character  set  other  than the ones definable by LESS-
       CHARSET.  In this case,  the  environment  variable  LESS-
       CHARDEF  can be used to define a character set.  It should
       be set to a string where each character in the string rep-
       resents one character in the character set.  The character
       "." is used for a normal character, "c" for  control,  and
       "b"  for binary.  A decimal number may be used for repeti-
       tion.  For example, "bccc4b." would mean  character  0  is
       binary,  1, 2 and 3 are control, 4, 5, 6 and 7 are binary,
       and 8 is normal.  All characters after the last are  taken
       to  be  the  same as the last, so characters 9 through 255
       would be normal.   (This  is  an  example,  and  does  not



                     Version 340: 27 Apr 1999                  20





LESS(1)                                                   LESS(1)


       necessarily represent any real character set.)

       This table shows the value of LESSCHARDEF which is equiva-
       lent to each of the possible values for LESSCHARSET:

            ascii     8bcccbcc18b95.b
            dos       8bcccbcc12bc5b95.b.
            ebcdic    5bc6bcc7bcc41b.9b7.9b5.b..8b6.10b6.b9.7b
                      9.8b8.17b3.3b9.7b9.8b8.6b10.b.b.b.
            iso8859   8bcccbcc18b95.33b.
            koi8-r    8bcccbcc18b95.b128.
            latin1    8bcccbcc18b95.33b.
            next      8bcccbcc18b95.bb125.bb

       If neither LESSCHARSET nor LESSCHARDEF is  set,  but  your
       system  supports  the  _s_e_t_l_o_c_a_l_e  interface, _l_e_s_s will use
       setlocale to determine the character  set.   setlocale  is
       controlled  by  setting  the  LANG or LC_CTYPE environment
       variables.

       Control and binary characters are  displayed  in  standout
       (reverse  video).   Each  such  character  is displayed in
       caret notation if possible (e.g. ^A for control-A).  Caret
       notation is used only if inverting the 0100 bit results in
       a normal printable character.  Otherwise, the character is
       displayed  as a hex number in angle brackets.  This format
       can be changed by setting the LESSBINFMT environment vari-
       able.   LESSBINFMT  may begin with a "*" and one character
       to select the display attribute: "*k" is blinking, "*d" is
       bold,  "*u"  is  underlined, "*s" is standout, and "*n" is
       normal.  If LESSBINFMT does not begin with a  "*",  normal
       attribute  is  assumed.   The remainder of LESSBINFMT is a
       string which may include one printf-style escape  sequence
       (a % followed by x, X, o, d, etc.).  For example, if LESS-
       BINFMT is "*u[%x]", binary  characters  are  displayed  in
       underlined   hexadecimal   surrounded  by  brackets.   The
       default if no LESSBINFMT is specified is "*s<%X>".


PPRROOMMPPTTSS
       The -P option allows you to  tailor  the  prompt  to  your
       preference.   The  string  given to the -P option replaces
       the specified prompt string.  Certain  characters  in  the
       string are interpreted specially.  The prompt mechanism is
       rather complicated to provide flexibility, but  the  ordi-
       nary  user need not understand the details of constructing
       personalized prompt strings.

       A percent sign followed by a single character is  expanded
       according to what the following character is:

       %b_X    Replaced  by the byte offset into the current input
              file.  The b is  followed  by  a  single  character
              (shown  as  _X above) which specifies the line whose



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LESS(1)                                                   LESS(1)


              byte offset is to be used.  If the character  is  a
              "t", the byte offset of the top line in the display
              is used, an "m" means use the middle  line,  a  "b"
              means use the bottom line, a "B" means use the line
              just after the bottom line, and a "j" means use the
              "target" line, as specified by the -j option.

       %B     Replaced by the size of the current input file.

       %d_X    Replaced  by the page number of a line in the input
              file.  The line to be used is determined by the  _X,
              as with the %b option.

       %D     Replaced  by the number of pages in the input file,
              or equivalently, the page number of the  last  line
              in the input file.

       %E     Replaced by the name of the editor (from the VISUAL
              environment variable,  or  the  EDITOR  environment
              variable  if  VISUAL is not defined).  See the dis-
              cussion of the LESSEDIT feature below.

       %f     Replaced by the name of the current input file.

       %i     Replaced by the index of the current  file  in  the
              list of input files.

       %l_X    Replaced  by the line number of a line in the input
              file.  The line to be used is determined by the  _X,
              as with the %b option.

       %L     Replaced by the line number of the last line in the
              input file.

       %m     Replaced by the total number of input files.

       %p_X    Replaced by the  percent  into  the  current  input
              file.  The line used is determined by the _X as with
              the %b option.

       %s     Same as %B.

       %t     Causes any trailing spaces to be removed.   Usually
              used  at the end of the string, but may appear any-
              where.

       %x     Replaced by the name of the next input file in  the
              list.

       If  any  item  is  unknown  (for example, the file size if
       input is a pipe), a question mark is printed instead.

       The format of the prompt string can be  changed  depending
       on  certain  conditions.   A  question  mark followed by a



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LESS(1)                                                   LESS(1)


       single character acts like an "IF": depending on the  fol-
       lowing character, a condition is evaluated.  If the condi-
       tion is true, any characters following the  question  mark
       and  condition  character, up to a period, are included in
       the prompt.  If the condition is  false,  such  characters
       are  not included.  A colon appearing between the question
       mark and the period can be used to  establish  an  "ELSE":
       any  characters  between  the  colon  and  the  period are
       included in the string if and only if the IF condition  is
       false.   Condition  characters  (which  follow  a question
       mark) may be:

       ?a     True if any characters have been  included  in  the
              prompt so far.

       ?b_X    True  if  the  byte offset of the specified line is
              known.

       ?B     True if the size of current input file is known.

       ?d_X    True if the page number of the  specified  line  is
              known.

       ?e     True if at end-of-file.

       ?f     True  if  there  is  an input filename (that is, if
              input is not a pipe).

       ?l_X    True if the line number of the  specified  line  is
              known.

       ?L     True  if  the  line  number of the last line in the
              file is known.

       ?m     True if there is more than one input file.

       ?n     True if this is the first prompt  in  a  new  input
              file.

       ?p_X    True  if the percent into the current input file of
              the specified line is known.

       ?s     Same as "?B".

       ?x     True if there is a next input file (that is, if the
              current input file is not the last one).

       Any characters other than the special ones (question mark,
       colon, period, percent, and  backslash)  become  literally
       part  of the prompt.  Any of the special characters may be
       included in the prompt literally by preceding  it  with  a
       backslash.

       Some examples:



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LESS(1)                                                   LESS(1)


       ?f%f:Standard input.

       This  prompt  prints the filename, if known; otherwise the
       string "Standard input".

       ?f%f .?ltLine %lt:?pt%pt\%:?btByte %bt:-...

       This prompt would print the filename, if known.  The file-
       name  is  followed by the line number, if known, otherwise
       the percent if known, otherwise the byte offset if  known.
       Otherwise,  a  dash  is printed.  Notice how each question
       mark has a matching period, and how the % after the %pt is
       included literally by escaping it with a backslash.

       ?n?f%f .?m(file %i of %m) ..?e(END) ?x- Next\: %x..%t

       This  prints the filename if this is the first prompt in a
       file, followed by the "file N of N" message  if  there  is
       more than one input file.  Then, if we are at end-of-file,
       the string "(END)" is printed followed by the name of  the
       next  file, if there is one.  Finally, any trailing spaces
       are truncated.  This is the default  prompt.   For  refer-
       ence,  here are the defaults for the other two prompts (-m
       and -M respectively).  Each is broken into two lines  here
       for readability only.

       ?n?f%f .?m(file %i of %m) ..?e(END) ?x- Next\: %x.:
            ?pB%pB\%:byte %bB?s/%s...%t

       ?f%f .?n?m(file %i of %m) ..?ltline %lt?L/%L. :byte %bB?s/%s. .
            ?e(END) ?x- Next\: %x.:?pB%pB\%..%t

       And here is the default message produced by the = command:

       ?f%f .?m(file %i of %m) .?ltline %lt?L/%L. .
            byte %bB?s/%s. ?e(END) :?pB%pB\%..%t

       The prompt expansion features are also  used  for  another
       purpose:  if  an environment variable LESSEDIT is defined,
       it is used as the command to be executed when the  v  com-
       mand  is  invoked.  The LESSEDIT string is expanded in the
       same way as the prompt strings.   The  default  value  for
       LESSEDIT is:

            %E ?lm+%lm. %f

       Note that this expands to the editor name, followed by a +
       and the line number, followed by the file name.   If  your
       editor  does  not  accept the "+linenumber" syntax, or has
       other differences in invocation syntax, the LESSEDIT vari-
       able can be changed to modify this default.






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LESS(1)                                                   LESS(1)


SSEECCUURRIITTYY
       When the environment variable LESSSECURE is set to 1, _l_e_s_s
       runs in a "secure" mode.  This means  these  features  are
       disabled:

              !      the shell command

              |      the pipe command

              :e     the examine command.

              v      the editing command

              s  -o  log files

              -k     use of lesskey files

              -t     use of tags files

                     metacharacters in filenames, such as *

                     filename completion (TAB, ^L)

       Less  can  also  be compiled to be permanently in "secure"
       mode.


EENNVVIIRROONNMMEENNTT VVAARRIIAABBLLEESS
       Environment variables may be specified either in the  sys-
       tem environment as usual, or in a _l_e_s_s_k_e_y (1) file.

       COLUMNS
              Sets  the  number  of columns on the screen.  Takes
              precedence over the number of columns specified  by
              the  TERM  variable.   (But if you have a windowing
              system which supports TIOCGWINSZ or  WIOCGETD,  the
              window  system's  idea  of  the  screen  size takes
              precedence over the LINES and  COLUMNS  environment
              variables.)

       EDITOR The name of the editor (used for the v command).

       HOME   Name  of  the user's home directory (used to find a
              lesskey file on Unix systems).

       HOMEDRIVE, HOMEPATH
              Concatenation of the HOMEDRIVE and  HOMEPATH  envi-
              ronment  variables  is  the name of the user's home
              directory if the HOME variable is not set (only  in
              the Windows version).

       INIT   Name  of  the user's init directory (used to find a
              lesskey file on OS/2 systems).




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LESS(1)                                                   LESS(1)


       LANG   Language for determining the character set.

       LC_CTYPE
              Language for determining the character set.

       LESS   Options which are passed to _l_e_s_s automatically.

       LESSBINFMT
              Format for  displaying  non-printable,  non-control
              characters.

       LESSCHARDEF
              Defines a character set.

       LESSCHARSET
              Selects a predefined character set.

       LESSCLOSE
              Command  line  to invoke the (optional) input-post-
              processor.

       LESSECHO
              Name of the lessecho program (default  "lessecho").
              The  lessecho program is needed to expand metachar-
              acters, such as * and ?, in filenames on Unix  sys-
              tems.

       LESSEDIT
              Editor  prototype  string (used for the v command).
              See discussion under PROMPTS.

       LESSKEY
              Name of the default lesskey(1) file.

       LESSMETACHARS
              List of characters which are considered  "metachar-
              acters" by the shell.

       LESSMETAESCAPE
              Prefix  which less will add before each metacharac-
              ter in a command  sent  to  the  shell.   If  LESS-
              METAESCAPE  is an empty string, commands containing
              metacharacters will not be passed to the shell.

       LESSOPEN
              Command line to invoke the (optional) input-prepro-
              cessor.

       LESSSECURE
              Runs  less  in "secure" mode.  See discussion under
              SECURITY.

       LESSSEPARATOR
              String to  be  appended  to  a  directory  name  in



                     Version 340: 27 Apr 1999                  26





LESS(1)                                                   LESS(1)


              filename completion.

       LINES  Sets  the  number  of  lines  on the screen.  Takes
              precedence over the number of  lines  specified  by
              the  TERM  variable.   (But if you have a windowing
              system which supports TIOCGWINSZ or  WIOCGETD,  the
              window  system's  idea  of  the  screen  size takes
              precedence over the LINES and  COLUMNS  environment
              variables.)

       PATH   User's  search path (used to find a lesskey file on
              MS-DOS and OS/2 systems).

       SHELL  The shell used to execute the ! command, as well as
              to expand filenames.

       TERM   The type of terminal on which _l_e_s_s is being run.

       VISUAL The name of the editor (used for the v command).


SSEEEE AALLSSOO
       lesskey(1)


WWAARRNNIINNGGSS
       The  =  command  and prompts (unless changed by -P) report
       the line number of the line at the top of the screen,  but
       the  byte  and  percent  of  the line at the bottom of the
       screen.

       If the :e command is used to name more than one file,  and
       one of the named files has been viewed previously, the new
       files may be entered into the list in an unexpected order.

       On  certain  older terminals (the so-called "magic cookie"
       terminals), search highlighting will  cause  an  erroneous
       display.   On  such terminals, search highlighting is dis-
       abled by default to avoid possible problems.

       In certain cases, when search highlighting is enabled  and
       a  search  pattern  begins  with  a  ^, more text than the
       matching string may be highlighted.   (This  problem  does
       not  occur  when less is compiled to use the POSIX regular
       expression package.)

       On some systems, _s_e_t_l_o_c_a_l_e claims that ASCII characters  0
       thru  31 are control characters rather than binary charac-
       ters.  This causes _l_e_s_s to  treat  some  binary  files  as
       ordinary,  non-binary  files.  To workaround this problem,
       set the environment variable LESSCHARSET  to  "ascii"  (or
       whatever character set is appropriate).

       The   MS-DOS   and   Windows  versions  sometimes  display



                     Version 340: 27 Apr 1999                  27





LESS(1)                                                   LESS(1)


       incorrect highlighting when  lines  are  longer  than  the
       screen width.

       See  http://www.flash.net/~marknu/less for the latest list
       of known bugs in this version of less.


CCOOPPYYRRIIGGHHTT
       Copyright (C) 1999  Mark Nudelman

       less is part of the GNU project and is free software;  you
       can  redistribute  it  and/or modify it under the terms of
       the GNU General Public License as published  by  the  Free
       Software Foundation; either version 2, or (at your option)
       any later version.

       less is distributed in the hope that it  will  be  useful,
       but  WITHOUT  ANY  WARRANTY; without even the implied war-
       ranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR  PUR-
       POSE.   See  the  GNU  General  Public  License  for  more
       details.

       You should have received a copy of the GNU General  Public
       License  along  with  less; see the file COPYING.  If not,
       write to the Free Software Foundation,  59  Temple  Place,
       Suite 330, Boston, MA  02111-1307, USA.


AAUUTTHHOORR
       Mark Nudelman <marknu@flash.net>
       Send  bug  reports  or comments to the above address or to
       bug-less@gnu.org.

























                     Version 340: 27 Apr 1999                  28


